Re: [PATCH 2/2] [NOT-FOR-MERGE] Add qtest for migration over RDMA

[Fabiano Rosas <farosas@suse.de>]

Li Zhijian via <qemu-devel@nongnu.org> writes:

> This qtest requirs there is RXE link in the host.
>
> Here is an example to show how to add this RXE link:
> $ ./new-rdma-link.sh
> 192.168.22.93
>
> Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
> ---
> The RDMA migration was broken again...due to lack of sufficient test/qtest.
>
> It's urgly to add and execute a script to establish an RDMA link in
> the C program. If anyone has a better suggestion, please let me know.
>
> $ cat ./new-rdma-link.sh
> get_ipv4_addr() {
>         ip -4 -o addr show dev "$1" |
>                 sed -n 's/.*[[:blank:]]inet[[:blank:]]*\([^[:blank:]/]*\).*/\1/p'
> }
>
> has_soft_rdma() {
>         rdma link | grep -q " netdev $1[[:blank:]]*\$"
> }
>
> start_soft_rdma() {
>         local type
>
>         modprobe rdma_rxe || return $?
>         type=rxe
>         (
>                 cd /sys/class/net &&
>                         for i in *; do
>                                 [ -e "$i" ] || continue
>                                 [ "$i" = "lo" ] && continue
>                                 [ "$(<"$i/addr_len")" = 6 ] || continue
>                                 [ "$(<"$i/carrier")" = 1 ] || continue
>                                 has_soft_rdma "$i" && break
>                                 rdma link add "${i}_$type" type $type netdev "$i" && break
>                         done
>                 has_soft_rdma "$i" && echo $i
>         )
>
> }
>
> rxe_link=$(start_soft_rdma)
> [[ "$rxe_link" ]] && get_ipv4_addr $rxe_link
>
> Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
> ---
>  tests/qtest/migration/new-rdma-link.sh |  34 ++++++++
>  tests/qtest/migration/precopy-tests.c  | 103 +++++++++++++++++++++++++
>  2 files changed, 137 insertions(+)
>  create mode 100644 tests/qtest/migration/new-rdma-link.sh
>
> diff --git a/tests/qtest/migration/new-rdma-link.sh b/tests/qtest/migration/new-rdma-link.sh
> new file mode 100644
> index 00000000000..ca20594eaae
> --- /dev/null
> +++ b/tests/qtest/migration/new-rdma-link.sh
> @@ -0,0 +1,34 @@
> +#!/bin/bash
> +
> +# Copied from blktests
> +get_ipv4_addr() {
> +	ip -4 -o addr show dev "$1" |
> +		sed -n 's/.*[[:blank:]]inet[[:blank:]]*\([^[:blank:]/]*\).*/\1/p'
> +}
> +
> +has_soft_rdma() {
> +	rdma link | grep -q " netdev $1[[:blank:]]*\$"
> +}
> +
> +start_soft_rdma() {
> +	local type
> +
> +	modprobe rdma_rxe || return $?
> +	type=rxe
> +	(
> +		cd /sys/class/net &&
> +			for i in *; do
> +				[ -e "$i" ] || continue
> +				[ "$i" = "lo" ] && continue
> +				[ "$(<"$i/addr_len")" = 6 ] || continue
> +				[ "$(<"$i/carrier")" = 1 ] || continue
> +				has_soft_rdma "$i" && break
> +				rdma link add "${i}_$type" type $type netdev "$i" && break
> +			done
> +		has_soft_rdma "$i" && echo $i
> +	)
> +
> +}
> +
> +rxe_link=$(start_soft_rdma)
> +[[ "$rxe_link" ]] && get_ipv4_addr $rxe_link
> diff --git a/tests/qtest/migration/precopy-tests.c b/tests/qtest/migration/precopy-tests.c
> index 162fa695318..d2a1c9c9438 100644
> --- a/tests/qtest/migration/precopy-tests.c
> +++ b/tests/qtest/migration/precopy-tests.c
> @@ -98,6 +98,105 @@ static void test_precopy_unix_dirty_ring(void)
>      test_precopy_common(&args);
>  }
>  
> +static int new_rdma_link(char *buffer) {
> +    // Copied from blktests
> +    const char *script =
> +        "#!/bin/bash\n"
> +        "\n"
> +        "get_ipv4_addr() {\n"
> +        "    ip -4 -o addr show dev \"$1\" |\n"
> +        "    sed -n 's/.*[[:blank:]]inet[[:blank:]]*\\([^[:blank:]/]*\\).*/\\1/p'\n"
> +        "}\n"
> +        "\n"
> +        "has_soft_rdma() {\n"
> +        "    rdma link | grep -q \" netdev $1[[:blank:]]*\\$\"\n"
> +        "}\n"
> +        "\n"
> +        "start_soft_rdma() {\n"
> +        "    local type\n"
> +        "\n"
> +        "    modprobe rdma_rxe || return $?\n"
> +        "    type=rxe\n"
> +        "    (\n"
> +        "        cd /sys/class/net &&\n"
> +        "        for i in *; do\n"
> +        "            [ -e \"$i\" ] || continue\n"
> +        "            [ \"$i\" = \"lo\" ] && continue\n"
> +        "            [ \"$(<$i/addr_len)\" = 6 ] || continue\n"
> +        "            [ \"$(<$i/carrier)\" = 1 ] || continue\n"
> +        "            has_soft_rdma \"$i\" && break\n"
> +        "            rdma link add \"${i}_$type\" type $type netdev \"$i\" && break\n"
> +        "        done\n"
> +        "        has_soft_rdma \"$i\" && echo $i\n"
> +        "    )\n"
> +        "}\n"
> +        "\n"
> +        "rxe_link=$(start_soft_rdma)\n"
> +        "[[ \"$rxe_link\" ]] && get_ipv4_addr $rxe_link\n";
> +
> +    char script_filename[] = "/tmp/temp_scriptXXXXXX";
> +    int fd = mkstemp(script_filename);
> +    if (fd == -1) {
> +        perror("Failed to create temporary file");
> +        return 1;
> +    }
> +
> +    FILE *fp = fdopen(fd, "w");
> +    if (fp == NULL) {
> +        perror("Failed to open file stream");
> +        close(fd);
> +        return 1;
> +    }
> +    fprintf(fp, "%s", script);
> +    fclose(fp);
> +
> +    if (chmod(script_filename, 0700) == -1) {
> +        perror("Failed to set execute permission");
> +        return 1;
> +    }
> +
> +    FILE *pipe = popen(script_filename, "r");
> +    if (pipe == NULL) {
> +        perror("Failed to run script");
> +        return 1;
> +    }
> +
> +    int idx = 0;
> +    while (fgets(buffer + idx, 128 - idx, pipe) != NULL) {
> +        idx += strlen(buffer);
> +    }
> +    if (buffer[idx - 1] == '\n')
> +        buffer[idx - 1] = 0;
> +
> +    int status = pclose(pipe);
> +    if (status == -1) {
> +        perror("Error reported by pclose()");
> +    } else if (!WIFEXITED(status)) {
> +        printf("Script did not terminate normally\n");
> +    }
> +
> +    remove(script_filename);
> +
> +    return 0;
> +}
> +
> +static void test_precopy_rdma_plain(void)
> +{
> +    char buffer[128] = {};
> +
> +    if (new_rdma_link(buffer))
> +        return;
> +
> +    g_autofree char *uri = g_strdup_printf("rdma:%s:7777", buffer);
> +
> +    MigrateCommon args = {
> +        .listen_uri = uri,
> +        .connect_uri = uri,
> +    };
> +
> +    test_precopy_common(&args);
> +}
> +
>  static void test_precopy_tcp_plain(void)
>  {
>      MigrateCommon args = {
> @@ -968,6 +1067,10 @@ static void migration_test_add_precopy_smoke(MigrationTestEnv *env)
>                         test_multifd_tcp_uri_none);
>      migration_test_add("/migration/multifd/tcp/plain/cancel",
>                         test_multifd_tcp_cancel);
> +#ifdef CONFIG_RDMA
> +    migration_test_add("/migration/precopy/rdma/plain",
> +                       test_precopy_rdma_plain);
> +#endif
>  }
>  
>  void migration_test_add_precopy(MigrationTestEnv *env)

Thanks, that's definitely better than nothing. I'll experiment with this
locally, see if I can at least run it before sending a pull request.